Buggy code:
public class ProxyControlGui extends LogicControllerGui implements ActionListener , FocusListener , KeyListener , JMeterGUIComponent , UnsharedComponent { private static transient Logger log = LoggingManager . getLoggerForClass ( ) ; private JTextField portField ; private JCheckBox httpHeaders ; private JComboBox groupingMode ; private JCheckBox addAssertions ; private JCheckBox useKeepAlive ; private JComboBox targetNodes ; private DefaultComboBoxModel targetNodesModel ; private ProxyControl model ; private JTable excludeTable ; private PowerTableModel excludeModel ; private JTable includeTable ; private PowerTableModel includeModel ; private static final String CHANGE_TARGET = "change_target" ; private JButton stop ; private JButton start ; private JButton restart ; private static final String STOP = "stop" ; private static final String START = "start" ; private static final String RESTART = "restart" ; private static final String ADD_INCLUDE = "add_include" ; private static final String ADD_EXCLUDE = "add_exclude" ; private static final String DELETE_INCLUDE = "delete_include" ; private static final String DELETE_EXCLUDE = "delete_exclude" ; private static final String INCLUDE_COL = JMeterUtils . getResString ( "patterns_to_include" ) ; private static final String EXCLUDE_COL = JMeterUtils . getResString ( "patterns_to_exclude" ) ; public ProxyControlGui ( ) { } public TestElement createTestElement ( ) { } protected ProxyControl makeProxyControl ( ) { } public void modifyTestElement ( TestElement el ) { } protected void setIncludeListInProxyControl ( ProxyControl element ) { } protected void setExcludeListInProxyControl ( ProxyControl element ) { } private List getDataList ( PowerTableModel model , String colName ) { } public String getStaticLabel ( ) { } public Collection getMenuCategories ( ) { } public void configure ( TestElement element ) { } private void populateTable ( PowerTableModel model , PropertyIterator iter ) { } public void focusLost ( FocusEvent e ) { } public void focusGained ( FocusEvent e ) { } public void actionPerformed ( ActionEvent action ) { } private void startProxy ( ) { } private void enableRestart ( ) { } public void keyPressed ( KeyEvent e ) { } public void keyTyped ( KeyEvent e ) { } public void keyReleased ( KeyEvent e ) { } private void init ( ) { } private JPanel createControls ( ) { } private JPanel createPortPanel ( ) { } private JPanel createTargetPanel ( ) { targetNodesModel = new DefaultComboBoxModel ( ) ; targetNodes = new JComboBox ( targetNodesModel ) ; targetNodes . setActionCommand ( ProxyControlGui . CHANGE_TARGET ) ; JLabel label = new JLabel ( JMeterUtils . getResString ( "proxy_target" ) ) ; label . setLabelFor ( targetNodes ) ; HorizontalPanel panel = new HorizontalPanel ( ) ; panel . add ( label ) ; panel . add ( targetNodes ) ; try { Class addToTree = Class . forName ( "org.apache.jmeter.gui.action.AddToTree" ) ; Class remove = Class . forName ( "org.apache.jmeter.gui.action.Remove" ) ; ActionListener listener = new ActionListener ( ) { public void actionPerformed ( ActionEvent e ) { reinitializeTargetCombo ( ) ; } } ; ActionRouter ar = ActionRouter . getInstance ( ) ; ar . addPostActionListener ( addToTree , listener ) ; ar . addPostActionListener ( remove , listener ) ; } catch ( ClassNotFoundException e ) { <START_BUG> throw new Error ( e ) ; <END_BUG> } return panel ; } private JPanel createGroupingPanel ( ) { } private JPanel createIncludePanel ( ) { } private JPanel createExcludePanel ( ) { } private JPanel createTableButtonPanel ( String addCommand , String deleteCommand ) { } private void reinitializeTargetCombo ( ) { } private void buildNodesModel ( JMeterTreeNode node , String parent_name , int level ) { } private String spaces ( int level ) { } public void setNode ( JMeterTreeNode node ) { } }

Fix:
throw new Error ( e . toString ( ) ) ;